The present invention relates to a vehicle-body structure of a vehicle and a manufacturing method of the same.
Vehicles, such as automotive vehicles, are required to increase the rigidity of a vehicle body in order to improve the comfortable ride and the safety. Japanese Utility Model Laid-Open publication Nos. 59-182472 and 60-097673, for example, disclose structures for increasing the rigidity in which a reinforcing member is provided in a closed-section portion formed by a vehicle-body forming member.
The first one of the above-described patent publications discloses the structure in which the bulkhead is arranged in a bamboo-joint shape in the closed-section portion of the side sill formed by the side sill outer and the side sill inner, and the flanges formed at its periphery are joined to the inner faces of the side sill outer and the side sill inner by both spot welding and an adhesive agent.
The second one of the above-described patent publications discloses the structure in which the bulkhead is arranged in the bamboo-joint shape in the closed-section portion of the front suspension member formed by the upper member and the lower member, and the flanges formed at its periphery are joined to the inner face of the upper member by an adhesive agent for structure.
According to the structures disclosed in the above-described patent publications, however, there is a concern that while improvement of the rigidity is achieved, vibrations occurring at various portions of the vehicle may not be effectively restrained from transmitting to the inside of the vehicle compartment in some cases depending on arrangement positions, shapes, and the like. Therefore, further improvement of the vehicle-body structure has been required in order to properly restrain vibration transmission to passengers for improving the comfortable ride and reducing noises.